The Android army is coming. The invasion is for real this time.

Google (NASDAQ:GOOG) and its Android software for mobile phones has never been available on the leading American networks: AT&T (NYSE:T) and Verizon (NYSE:VZ) Wireless. Instead, Android announcements have trickled out from third-place network provider Sprint Nextel (NYSE:S) and fourth-place also-ran T-Mobile. That makes sense because the two smaller providers are members of Google's Open Handset Alliance, which sets the standards for Android, while the big boys are not.

But now Verizon has committed itself to the Android cause, leaving AT&T behind to snuggle with the Apple (NASDAQ:AAPL) iPhone. Verizon will introduce a plurality of Android phones "within the next few weeks" with hardware from "leading handset manufacturers."

These new models will undoubtedly be straight-up smartphones at first, because that hardware format seems ideally suited to show what the Android can do. If Verizon hopes to sell any serious volume of Android phones, the company needs to show us why we should care about this new offering. More bare-bones handsets and upmarket netbooks running Android will follow later.

At the same time, Verizon kicked off a new marketing campaign aimed right at AT&T's iPhone-fueled network issues. Weak 3G coverage? "There’s a map for that," a voiceover quips as a map of AT&T and Verizon’s networks are displayed together. The takeaway is that Verizon promises five times more 3G coverage area. Maybe there was something in the water yesterday that inspired the world to gang up on Apple, because Microsoft (NASDAQ:MSFT) chose the same day to announce the latest version of Windows Mobile, while the next iPhone update is probably about eight months away. Will we remember this as the week when the iPhone's imposing stature in the mobile phone industry started to shrink?

Verizon will sell new Windows phones, too, as will nearly everyone else, and Verizon has upgraded its stable of high-end phone stallions to augment the BlackBerry Storm from Research In Motion (NASDAQ:RIMM) and compete more effectively in that segment. But the real winner here is Google. CEO Eric Schmidt is talking himself warm over Verizon's open attitude and robust network, noting that Verizon's philosophy "works very, very well with the Internet." Google profits when Internet traffic is on the rise, regardless of the technologies people use to go online. Androids don't pull people's arms out of their sockets when they lose.

Should Verizon even bother to land an iPhone deal when AT&T's exclusive contract runs out next year? I don't think so, but your mileage may vary. Share your insights in the comments below.

Google is a Motley Fool Rule Breakers pick. Apple is a Motley Fool Stock Advisor recommendation. Microsoft and Sprint Nextel are Motley Fool Inside Value selections. Try any of our Foolish newsletters today, free for 30 days.

Fool contributor Anders Bylund owns shares in Google, but he holds no other position in any of the companies discussed here. You can check out Anders' holdings and a concise bio if you like, and The Motley Fool is investors writing for investors.